https://www.ford-trucks.com/forums/showthread.php?t=1678640&goto=newpost
link to other thread above ^
Replaced upper and lower fuel filter checked fuel pressure was only 40 at idle added blue spring only 42 at idle motor has no power at all until you get up in rpms even in a hot tune idle is Shakey as all get out, and hesitates horribly pulled codes and now has cyl 2 and 4 contribution codes new ficm new ficm harness blue spring and new injector for cyl 7 all this started when I bought it it was missing real bad replaced injector for 7 then it ran great for a few hours and started the same thing again now for 2 and 4 need some advise on where to go from here this weekend I'm going to run the diesel out of a Jerry can and see if theres an issue with the tank if not I'm lost after that and my icp and ipr are normal same with vgt

 

Original pump on the frame rail? Killing injectors with low fuel pressure.

You Tube

 

That's where I'm leaning but how do I prove it without buying a new pump and being without results

 

At the current time frame, many people have been having issues with the foot in the fuel tank disintegrating and the debris can clog the line to the pump. The check for that is to put a 3/8 hose to the bottom inlet nipple on the HFCM into a can of diesel fuel and see what the fuel pressure is key-on.

Another thing, while you said you changed the spring, but what about the regulator seal, and is it in good condition now.

Sometimes you can tell a bad pump motor based on it sound key-on. Although that can take a trained ear.

 

I did replace it with the spring was going to do the Jerry can thing this weekend and pump does wine key on but can't tell if it's normal or not

 

Not sure if you're the original owner of the truck and know whether the pump has been replaced before; but assuming it hasn't, it's one of the few 1999 model trucks that hasn't. I'd go ahead and install a new pump, and if that doesn't fix it, just know that the pump in your 22-year old truck was going to fail soon anyway. Keep the old one as a spare.

 

no this is a 04 6.0 and it looks original

 

Oops, I saw 99 in your profile. Still, an original 04 pump is prolly due for a failure. I don't like throwing parts at a problem, but when it's one that needs to be replaced soon anyway, I'll do it. Install yourself and you've saved half the cost.

 

rarely do i go to a shop unless I can't actually do it I do it my self but you're probably right
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Well, not sure about "right" - the pump might not be your problem - but, IMHO, it's worth a roll of the dice, and they're not hard to install. The part is a bit overpriced though.

 

Where did you buy the blue spring kit?

 

Ford dealership, don't use the chinese stuff.

 

You can make this tool for checking fuel pressure. It simulates a WOT run without leaving the driveway.
The key to the WOT simulator is the orifice. You hook this up a the filter pressure test port and them start the
engine at idle and make note of the static pressure. Next you open the calve and recheck the pressure. The last
pressure is. what you would get if you make a WTO run down the road. This then saves you any ticket you
might get by going full throttle down the road.

The one end of the "T" goes to the pressure test port on the upper filter housing. The orifice end can be
plumbed into a bucket of any other catch can or even go right back into the tank.